From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CAFF5C3A59B for ; Fri, 30 Aug 2019 15:46:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 92F1A23407 for ; Fri, 30 Aug 2019 15:46:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ACtDIJSR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728258AbfH3PqA (ORCPT ); Fri, 30 Aug 2019 11:46:00 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:38464 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727304AbfH3PqA (ORCPT ); Fri, 30 Aug 2019 11:46:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=wePmmyRAqzc9E8AvYvRy4CjZhcBEJxH2FmSPiZPoaEw=; b=ACtDIJSRM2EBOX+MHFb+Pg7Gj okiQGHIbGoDwFEpUIcFKrJ5P2TzxRrH8kQt1x1ttlmn8Hi6EYwnOS5wxfPX12SyRasM7GrLFcfwGx SpmwqgAHfveVdSQRIdU/UNLxWv8nu5nF0S836rOWWjtWiQyyofMPsjTctBlFlFLwk0O+rjXPPnoeG 0IU3703HDn+vjNLkMF6/eqk5amnwC0IUBIaE9ezBMcoSxbwHmp0lqRizsJo4jiPkejwxITaV14R6V VyhLyMS9aa2J98Zbwpo/kX8fZcwV27B+kZWNwBCvhPEgnijY51i27p6dW51LFFz8No1uGrBKNHO6J 1NLVlItmg==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1i3j5z-0005dZ-2P; Fri, 30 Aug 2019 15:45:51 +0000 Date: Fri, 30 Aug 2019 08:45:51 -0700 From: Christoph Hellwig To: Joe Perches Cc: Gao Xiang , Chao Yu , Dan Carpenter , Christoph Hellwig , Greg Kroah-Hartman , devel@driverdev.osuosl.org, LKML , linux-erofs@lists.ozlabs.org, Chao Yu , Miao Xie , weidu.du@huawei.com, Fang Wei Subject: Re: [PATCH v2 2/7] erofs: some marcos are much more readable as a function Message-ID: <20190830154551.GA11571@infradead.org> References: <20190830030040.10599-1-gaoxiang25@huawei.com> <20190830030040.10599-2-gaoxiang25@huawei.com> <5b2ecf5cec1a6aa3834e9af41886a7fcb18ae86a.camel@perches.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5b2ecf5cec1a6aa3834e9af41886a7fcb18ae86a.camel@perches.com> User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 29, 2019 at 08:16:27PM -0700, Joe Perches wrote: > > - sizeof(__u32) * ((__count) - 1); }) > > +static inline unsigned int erofs_xattr_ibody_size(__le16 d_icount) > > +{ > > + unsigned int icount = le16_to_cpu(d_icount); > > + > > + if (!icount) > > + return 0; > > + > > + return sizeof(struct erofs_xattr_ibody_header) + > > + sizeof(__u32) * (icount - 1); > > Maybe use struct_size()? Declaring a variable that is only used for struct_size is rather ugly. But while we are nitpicking: you don't need to byteswap to check for 0, so the local variable could be avoided. Also what is that magic -1 for? Normally we use that for the deprecated style where a variable size array is declared using varname[1], but that doesn't seem to be the case for erofs.